Fatigue is a common complaint in rheumatic disorders and is one of the strongest predictors of physical dysfunction in patients with Fibromyalgia (FM) and other related disorders, rheumatoid arthritis (RA), osteoarthritis (OA), and systemic lupus erythematosus (SLE). However, research addressing the causes and mechanisms of fatigue is rare in rheumatic illnesses. The lack of scientific evidence focusing on the role of fatigue in rheumatic illness directly impacts on the ability of health care professionals to assess the presence, severity and trajectory of fatigue and to evaluate the relationship of fatigue with other symptoms of these disorders in order to provide appropriate treatment recommendations. Fatigue is one of the most commonly reported, yet least understood and unrelieved symptoms accompanying chronic illnesses. The primary objective of the proposed workshop is to establish a knowledge base of current information on fatigue in rheumatic illness that will be compared with the state of knowledge gained from studies of fatigue in cancer, HIV/AIDS, stroke, and MS. This process will serve to identify knowledge gaps concerning the role of fatigue in rheumatic illness. Directions for future fatigue research in rheumatic illness will be suggested incorporating research methodologies that have proven successful in other somatic disorders. To achieve these objectives, a group of renowned fatigue and sleep researchers drawn from a variety of scientific areas including neuroscience, physiology, immunology, and psychiatry/psychology, clinical practice, as well as representatives of public interest groups will be invited to attend a workshop to be held on March 18 and 19, 2004 at the Dolce Hamilton Park Conference Center in Florham Park, NJ. Presentations addressing definition, conceptualization, and assessment of fatigue in general will proceed state-of-the-art overviews of fatigue research in FM, RA, OA, SLE, cancer, HIV/AIDS, stroke, and MS, and will be followed by concentrated discussions in break-out groups. A position statement summarizing the results from this workshop will be produced at the conclusion of the meeting and disseminated via publication in a peer-reviewed journal. The collaborative and interactive nature of the proposed workshop will ensure that the recommendations generated will have a broad impact on the scientific community, and will generate collaborative, interactive research amongst scientists and clinicians with an interest in rheumatic illnesses.